This invention relates to a nozzle assembly for a trigger sprayer and more particularly to a nozzle assembly that incorporates a cam and cam follower for controlling the relative positions of a cap and a housing to selectively establish the flow condition of fluid discharged from the trigger sprayer.
A typical trigger sprayer has a housing incorporating a fluid chamber. A manually actuable trigger pumps fluid from a fluid source to the fluid chamber. A spinner at the outlet end of the fluid chamber has a swirl chamber that can impart a spray condition to fluid being discharged from the housing chamber. A cap is threaded onto the housing and the rotational position of the cap changes the flow condition of fluid from a spray condition to a stream condition. This is caused by the threaded connection of the cap to the housing in a typical helical threading configuration. In one threaded position of the cap, a spray condition is achieved with the fluid being discharged through an outlet orifice in the cap. As the cap is threaded relative to the housing, a stream character is introduced and with further threading of the cap, the influence of the stream condition increases while the influence of the spray character decreases. Still further threading of the cap achieves a stream only condition.
These threaded cap arrangements do not provide selective control that enables adjustment of the spray characteristic of the discharged fluid without influence from a stream characteristic and separately do not impart a gradually increasing stream condition with a corresponding gradually decreasing spray condition to be followed by a stream only condition that is maintained over a finite span of rotation of the cap.
Some efforts have been made to incorporate a cam and cam follower in a trigger sprayer. Malone U.S. Pat. No. 3,650,473 and Micheloff U.S. Pat. No. 4,234,128 represent examples of these efforts. In the Malone patent, only two spray conditions are established by the position of the cap relative to the spray body. These two conditions are a spray condition and a stream condition. In order to establish an "off" condition, it is necessary to operate a separate hinged cover. Also, in the Malone device, there are no variations of the spray condition without immediate influence from the stream condition.
In the Micheloff patent, the trigger sprayer works differently from the manner of the present invention. The Micheloff trigger sprayer discloses a cap that is rotatably mounted on a sprayer body, but there are neither threads nor camming means for moving the cap axially relative to the sprayer body or relative to a spinner. In one condition, the nozzle assembly is in an "off" condition. Upon rotation of the cap a flow condition is established. Further rotation of the cap establishes a stream condition. These different conditions are achieved by the changing communications between passageways on a core and passageways on a sleeve and when none of the passageways are in communication, fluid flow is blocked.
The nozzle assembly of the present invention provides a cap that is both rotatably and axially movable relative to a housing, the path of movement being determined by a cam slot and cam follower connection between the cap and housing. The configuration of the cam slot allows the user to create a spray that is variable in character with no influence by a stream condition as the cap is rotated through an initial path. Further rotation of the cap through a second path introduces a variable coarse spray in which the effect of the spray condition is gradually influenced by the introduction of a stream condition. As the cap is rotated toward the end of the second cam section, a stream condition is reached that has eliminated the influence of the spray condition. Finally, there is a third cam section where the stream-only condition is maintained with assurance that the cad will not jiggle back to a position that introduces influence from the spray condition.